Inelastic seismic energy spectra for soft soils: Application to Mexico City

Elastic and Inelastic Near-Fault Input Energy Spectra

“…The scaling operations summarized in Figure 1 are quite well established for the acceleration response spectra or design spectra. However, the effect of ζ and R on input energy spectra is not as distinct as in the acceleration response spectra (Quinde et al 2016, Decanini and Mollaioli 2001). We will investigate whether such scaling relations can be defined for near-fault elastic and inelastic input energy spectra in this study.…”

“…Exact description of elastic and inelastic input energy spectra for recorded earthquake ground motions is theoretically obtained by integrating the equation of motion over time for a class of SDOF systems (Zahrah and Hall 1984, Uang and Bertero 1990, Sucuoğlu and Nurtuğ 1995). Design input energy spectra for elastic or inelastic systems on the other hand can be estimated by two procedures: Either by employing prediction equations based on the site and source characteristics of ground motions recorded in the past as well as the SDOF response parameters obtained under these ground motions (Chapman 1999, Chou and Uang 2000, Chou and Uang 2003, Cheng et al 2014, Alıcı and Sucuoğlu 2016), or by developing practical scaling rules relating the elastic or inelastic system and energy response parameters with the intensity parameters of recorded ground motions (Akiyama 1988; Benavent-Climent et al 2002, 2010; Okur and Erberik 2012; McKevitt et al 1960; Fajfar and Fischinger 1990; Fajfar et al 1992, 1994; Vidic et al 1994; Amiri et al 2008; Decanini and Mollaioli 1998, 2001; Quinde et al 2016). In fact, the most practical approach for obtaining input energy spectra for inelastic systems with different damping values ( ζ ) and lateral strength ratios ( R ), which defines the ratio of the lateral elastic strength demand to the lateral strength capacity of the system, is applying scaling factors to a reference elastic input energy spectra derived for 5% damping.…”

A Study on Elastic Input Energy Spectra for Actual Earthquake Ground Motions at Stiff Soil Sites

“…In literature, many approximate formulas have been proposed for obtention of the maximum seismic input energy [19,22,[24][25][26][27][28]. Moreover, the seismic input energy spectra have been created for a specific strong ground motion and the input energy values of both elastic and inelastic systems have been obtained practically via these graphs [24,[37][38][39][40][41][42][43][44][45]. In brief definition, the seismic input energy spectra are the graphs which combine the maximum energy input values corresponds to different natural vibration periods of SDOF systems.…”

“…There are many factors (such as earthquake magnitude, closest distance from the seismic source, soil type, focal mechanism, damping ratio, type of hysteresis for the inelastic spectra, and etc.) which have an impact on the seismic input energy spectra [39,42,43]. The flowchart to obtain the input energy spectra is presented in Figure 3.…”

“…The obtention of input energy spectra offers an important advantage to determine the energy input to structures with the effect of ground motions. Peak ground acceleration, peak ground velocity, the ratio of peak ground acceleration to peak ground velocity, the duration and predominant periods of ground motions, fault type and mechanism, distance to the fault, the magnitude of ground motions and soil conditions were referred in many previous studies as specific parameters to obtain the seismic input energy spectra [19,25,28,[37][38][39][40][41][42][43][44]. Fajfar and Vidic [37], Sucuoglu and Nurtug [38], Decanini and Mollaioli [39], Manfredi [24], Benavent-Climent et al [40], López-Almansa et al [41], Dindar et al [42], Quinde et al [43], Alici and Sucuoglu [44] and Ozsarac et al [45] made pioneer and further investigations about the earthquake input energy spectra for both elastic and inelastic systems.…”